Steam trap



3 w. B. CLIFFORD ET AL 1,342,657

STEAM TRAP Filed Nov.7, 19:1

il iinew' Jzvenfors an-M . n w f nauseousduplication tiled present invention relates to steam more particularly to steam traps an enpansihle and contractible containing a thermostatic tluid.

"' class oi devices an enpansible diacanted within a trap body, and

. :3 s to close the outlet to the body when con ued therein, and to open to rovide for egress "for air and water of coin non ect of the present invention is to p rly and improve steam traps of this character in a manner to promote economy or .oduction and insure uniformity oi operaon this and other objects in view the is features of the invention consist in "tin novel features of construction coin ina one and arrangements of parts herein escribed and claimed, the advantages h will be obvious to those skilled in from the following description .i the accompanying drawings illustrating oreierred :torm oil the invention, Fig, 1 esents a section in elevation of the com d trap; and Fig. 2 is a similar section of combined cap and bellows unit removed the trap body. is trap shown in the illustrated embodioil the invention comprises a body por- Ilt) provided with an inlet connection l2 one an outlet connection it at the ft urn, 'l he outlet connection is formed re shape of a hexagonal nut internally u ended at id to :tacilitate its connection to return pipe oil. a steam system. The inlet nection i2 is threaded, and may be pro l with nut for connection with the or or steam consuming unit from a le term oi union. The upper portion o trap body is closed by a cap 18, which p ovided with or depending circumferential .nge EU, threadedly engaged at 22 with corresponding threads termed on the body. 'llhe opposing faces 24 at the uppei' cdge Oil the trap body and the cap are machined to term plane surfaces capable of sealing the interior oil the body against pressures employed.

lit will he observed tram the accompanying lid /, dcrlal it's.

drawings that the trap body is reasonably shallow and tree from abrupt curves which racllitates formation oi the body complete as a forged unit. it is intended that both the body and the cap shall each he forged of brass or suitable material, with such parts machined as may be necessary for an accurate lit. lln this connection it will he understood that either the body or cup or both might be cast without essentially afl'ecting the device or its mode of operation, although from the standpoint of producing a leak-proof body and cap the forging is superior to the casting, which, in the absence of precautionary methods, may be porous.

The cap 18 is provided with a raised henagonal portion as for attachment to the body, and interiorly is provided with a circular recess 28 of reduced diameter which fits the reduced neck portion 30 of a metallic bellows 32 The engagement oi the reduced neck portion 30 with the recess 28 serves to center the bellows unit with respect to the cap, and the two are bonded in permanent relationship by a film of solder 33, extending outwardly from the circular recess between the contacting surfaces of the cap and the first bellows told. The metallic bellows anchored at one end to the cap is integrally closed at its lower or free end 35, the end tit wall forming a portion of the cupped tube from which the bellows is constructed. This end wall, which is preferably thicker by a substantial amount than the thickness of the corrugated wall, is shaped to form a tapered valve member 37, located centrally of the bellows unit. after assembled with the trap body, the tapered valve 3'? is located centrally and above an outlet port 40 formed in the lower portion of the trap body, and designed in cooperation with the valve 3? to automatically control the egress of air and water oil con densation from the trap. The automatic op eration of the bellows unit is secured as described in the previous patent of Clifiord No. 1,816,142, by locating within the bellows unit water under a vacuum normally sulti cient to maintain the unit in the contracted position shown at temperatures beneath the When the unit is there boiling point. 'When the water within the bellows unit, on the other hand, is converted into steam by the presence of steam in the trap body and contact with the thin walls of 1 the unit, the vacuum is broken and the bellows unit, due to the equalization of pressure within and without, tends to assume a free I length, causing the-valve 37 to seat upon the inserted in and removed from the trap body by insertion and removal of the cap without dismantling the body from the line. Furthermore, the thermostatic unit, due to the fact that the bottom portion of the valve is integral with the bellows folds is free from soldered or bonded joints aifording liability for leakage and presentin opportunity for erosion from the action of the steam. The only bonded joint is the joint between the upper portion of the metallic bellows and the cap, com letely covered by the opposing walls of t e cap and bellows, and enclosed and removed from the erosive action of the steam.

In producing this thermostatic unit, as described in our co-pendin application filed of evendate herewith, t'e bellows unitis assembled with the cap, an opening being formed through the tip of the valve, and thereafter the unit is thermostatically filled and sealed by a solder button 42, located in the valve tip and closing the relatively small opening therethrough.

This type of steam trap is-economical to manufacture because the cap is made to complement the metallic bellows in producing a a complete thermostatic unit, and in addition the valve is formed from the material at the closed end of the unit rather than a separate element. Moreover, by the production of a thermostatic unit comparatively shallow in depth, and seating this unit directly in the cap, .a corresponding savlng in the depth of the trap body may be produced, which results in the saving in weight of material as compared with previous constructions of this character employing metallic bellows as the thermostatic element. A corresponding unit of equivalent capacity employing a metallic diaphragm would require a much greater diameter to obtain the necessary action, with a consequently greater diameter of body and increase in weight.

What is claimed is:

1.- A steam trap comprising a trap body having an outlet port, an im erforate and one-piece forged cap detacha ly connected with the body for sealing the upper portion of the chamber therein, a metallic bellows having one end integrally closed except for the provision of a hermetically sealed opens ing therein, the bellows contacting about its open end directly with the interior seamless surface of the cap and bonded thereto to seal the space encompassed by the bellows and cap, a valve at the integral closed end of the bellows aligned with the outlet port when the cap is assembled with the body, and thermostatic fluid sealed within the expansible chamber formed by the cap and bellows to cause movement of the valve end of the bellows upon variation of temperature within the trap body.

2. A steam trap comprising a trap body having an outlet port, an imperforate and seamless cap detachably connected with the body for sealing the upper portion of the chamber therein and having a central recess interiorly thereof and a comparatively flat surface surrounding the recess, a metallic bellows having one end integrally closed except for the provision of a hermetically sealed opening therein, the bellows having an opposite open end extending into the recess and positioned thereby and bonded directly to the interior surface of the cap in the area surrounding the recess to seal the space encompassed by the bellows and cap, a valve at the integral closed end of the bellows aligned with the outlet port when the cap is assem-- bled with the body, and thermostatic fluid sealed within the expansible chamber formed by the cap and bellows to cause movement of the valve end of the bellows upon variation of temperatre within the trap bod 3. A steam trap comprising a trap bo y having an outlet port, an imperforate and one-piece cap detachably connected with the body for sealing the upper portion of the chamber therein, a metallic bellows having one end integrally closed and contacting at its opposite open end directly with the interior and seamless surface of the cap and bonded thereto to seal the space encompassed by the bellows and cap, the integral closed end of the bellows being formed it provide a tapered valve extension aligned with the outlet port when the cap is assembled with the body and having an opening therethrough closed with solder or its equivalent to seal the space within the bellows, and thermostatic fluid sealed in the chamber formed by the cap and bellows.

In testimony whereof we have signed our names to this specification.

WALTER B. oLIFFoRn. JOHN E. WOODS. I 

